A 54 year old man presented with a three week history of cough, breathlessness, chest pain, and peripheral oedema; he had lost 38 kg in weight over six months. Computed tomography showed a hilar mass compressing the right main bronchus, which caused upper lobe collapse, a pleural effusion, and a large pericardial effusion (white arrows) compressing the heart (black arrows)⇑. Malignant effusion of lung adenocarcinoma origin was diagnosed on pericardiocentesis. Lung cancer is the commonest cause of malignant pericardial effusion. Symptoms are secondary to diastolic heart failure and prognosis is poor. Our patient returned three months later with progressive breathlessness and was transferred to a hospice for end of life care.